LANHAM, Md. (WNEW) — A Maryland man who allegedly impersonated a police officer after refusing to pull forward at a fast-food drive thru has been charged with DWI.

Anne Arundel County Police say Robert Knickerbocker, 47, ordered food at the Taco Bell, in the 500 block of Ritchie Highway in Severna Park, at about 2 a.m. Sunday. Store employees told police that Knickerbocker refused to pull forward to the next window, and instead remained in his Mercedes sedan and began acting belligerent.

Police say Knickerbocker, of Severna Park, was repeatedly blowing his car horn and cursing when officers arrived, and he told them he was a police officer with the Maryland Natural Resources Police.

Police say Knickerbocker’s breath smelled of alcohol, his eyes were glassy and his speech was mumbled and slurred. He also failed several field sobriety tests.

Police later learned that Knickerbocker is not a police officer with any department. However, Natural Resources Police say he is a volunteer reserve officer.

Natural Resources Police say he has been suspended, and his badge and uniform have been confiscated pending internal review.